This is La Jolla, after all, and everybody at one time or another seems to get deep into the perennial tradition that is surfing, even if only as observers. But this time of year, a species of small, silvery fish take to their version of the local pastime — and Birch Aquarium at Scripps Institution of Oceanography invites you to watch.

On April 1, Birch launched this year’s installment of its grunion run events, which center on the fishes’ seasonal egg-laying and take place only in Southern California. Naturalists guide participants through an interactive presentation and an egg hatch involving the beaching of perhaps thousands of females. Weather and tides permitting, the evenings continue with a beach exploration to witness the fish leave the eggs behind and catch a wave back to the sea. The events do not take place at the aquarium.

Grunion, which measure five to six inches in length, were known to the area’s Spanish settlers for the grunting noise they emit during spawning. The scientific name for the California grunion is Leuresthes tenuis, and this fish belongs to the family Atherinidae, commonly known as silversides.

The aquarium suggests bringing a flashlight and a warm jacket.

The remaining events will take place Thursday, April 17, Saturday, May 17 and Saturday, May 31 from 11 p.m. to 1 a.m. Additional events are scheduled Friday, May 16, Friday, May 30 and Saturday, June 14 from 10:30 p.m. to 12:30 a.m. Admission is $14 for aquarium members and $16 for the general public.

Patrons must be at least 6 years of age; children 6 to 13 must attend with a paying adult. Information on the venues is available at (858) 534-3474 or aquarium.ucsd.edu. Reservations must be made in advance by phone or online.

Birch Aquarium, at 2300 Expedition Way in La Jolla, is the public exploration center for the world-renowned Scripps Institution of Oceanography at UCSD. The present facility, which opened in 1992, features more than 60 habitats of fish and invertebrates from the Pacific Northwest to Mexico and beyond. An interactive museum showcases research discoveries by Scripps scientists on climate and ocean sciences.

Birch Aquarium has an annual attendance of more than 440,000, including 40,000 school children.

Birch Aquarium grunion run is under wayThis is La Jolla, after all, and everybody at one time or another seems to get deep into the perennial tradition that is surfing, even if only as observers. But this time of year, a species of smal...